Chrysler Dodge Caravan 2002 Manual page 1311

9 - 110 ENGINE 3.3/3.8L
VALVE SPRINGS (Continued)
(2) Follow the same procedure on the remaining 5
cylinders using the firing sequence 1-2-3-4-5-6. Make
sure piston in cylinder is at TDC on the valve
spring that is being covered.
(3) Remove spark plug adapter tool.
(4) Install rocker arms and shaft assembly. (Refer
to 9 - ENGINE/CYLINDER HEAD/ROCKER ARMS -
INSTALLATION)
(5) Install cylinder head covers. (Refer to 9 -
ENGINE/CYLINDER
COVER(S) - INSTALLATION)
(6) Install spark plugs and connect wires.
(7) Connect negative cable to battery.
ROCKER ARMS
DESCRIPTION
DESCRIPTION - ROCKER ARMS
The rocker arms are installed on the rocker arm
shaft. The rocker arms and shaft assembly is
attached to the cylinder head with seven bolts and
retainers. The rocker arms are made of stamped
steel.
DESCRIPTION - PUSHRODS
The pushrods are made of steel and are a hollow
design. The pushrods are positioned between the
hydraulic lifter and the rocker arm.
OPERATION
OPERATION - ROCKER ARMS
The rocker arm pivots on the rocker shaft. Rocker
arms are used to translate up and down motions pro-
vided by the camshaft, hydraulic lifter, and pushrod
on one end, into a down and up motions on the valve
stem on the opposing end.
OPERATION - PUSHRODS
The pushrod is a solid link between the hydraulic
lifter and the rocker arm. Also, the pushrod supplies
engine oil from the hydraulic lifter to the rocker arm.
HEAD/CYLINDER
REMOVAL - ROCKER ARMS AND SHAFT
(1) Remove the cylinder head cover(s). (Refer to 9 -
ENGINE/CYLINDER
COVER(S) - REMOVAL)
NOTE: Rocker arm shaft bolts are captured to the
shaft.
(2) Loosen the rocker shaft bolts (Fig. 40), rotating
one turn each, until all valve spring pressure is
HEAD
relieved.
(3) Remove the rocker arms and shaft assembly
(Fig. 40).
(4) For rocker arm disassembly procedures, (Refer
to 9 - ENGINE/CYLINDER HEAD/ROCKER ARMS -
DISASSEMBLY).
Fig. 40 ROCKER ARMS AND SHAFT
1 - ROCKER ARMS AND SHAFT ASSEMBLY
2 - ROCKER SHAFT BOLTS
DISASSEMBLY - ROCKER ARMS AND SHAFT
CAUTION: Do not attempt to drive the bolt from the
rocker shaft. This can damage the retainer and bolt
assembly.
(1) Remove the rocker arm retainer and bolt by
performing the following procedure:
(a) Using adjustable pliers, grip the edges of the
retainer (Fig. 41).
(b) Apply an upward force with a slight rocking
motion until the retainer disengages from shaft
(Fig. 41).
(2) Remove rocker arms (Fig. 42). Identify the
component locations for reassembly in original loca-
tions.
HEAD/CYLINDER
RS
HEAD